Document EP 2,264,860 describes an electric motor rotor comprising a tubular foliated assembly and “buried” magnets, i.e., not extended over the periphery of the rotor. Housings formed in this assembly each receive a group of permanent magnets, each group of permanent magnets forming a magnetic pole of the rotor. All of the magnets in a same group are covered, on each of their faces, with electrically insulating material designed to insulate the magnets from one another and relative to the foliated assembly.
Such a rotor is not fully satisfactory. Indeed, the addition of an insulating material surrounding the magnets individually on each of their faces increases the manufacturing cost of the rotor and makes the assembly method more complex.